Forming machine



Jan. 3, 1967 E. o. ACKER ETAL 3,295,345

FORMING MACHINE Filed Feb. 18, 1964 4 Sheets-Sheet 1 H E K m4 0 m 5 I2 .4' -JU ATTOP/VE'YS Jan. 3, 1967 E. o. ACKER ETAL 3,295,345

FORMING MACHINE Filed Feb. 18, 1964 4 Sheets-Sheet 2 INVENTORS (Fe/c a AC/(EQ, Ee/c 0. A 6K5? Me. 58 BY PLE-ASA/vr A K/MEALL Jan. 3, 1967 E. o. ACKER ETAL FORMING MACHI NE 4 SheetsSheet 5 Filed Feb. 18, 1964 EMP- 2 :9 O? M TA}; N K k E CK V CP W r QN .w M Fm E H p Tl E5f-5 United States Patent 3,295,345 FURMENG MACEHNE Eric 0. Acker, 4436 NW. 59th St, ()klahoma City, Gkla. 73118; Eric 0. Acker, $13, 7804 NW. 28th Terrace, Bethany, Okla. 73008; and Pleasant P. Kimball, 5912 NW. 50th, Oklahoma City, Okla. 73135 Filed Feb. 18, 1964, Ser. No. 347,992 8 Claims. (Cl. 72-24) This invention relates generally to improvements in material forming machines. More particularly, but not by way of limitation, this invention relates to improved machines for forming expanded metals.

Expanded metal forming machines constructed in the past have generally utilized a pair of mating dies alternately engaged and disengaged to form a sheet of material placed therebetween. Most often, one of the dies was arranged to be shifted longitudinally relative to the other die. Each time the dies were separated, the material being formed was fed a certain distance between the dies, depending upon the configuration desired in the finished product. Such machines were generally ruggedly constructed due to the high stresses placed on them and, consequently, included moving parts having a relatively high mass. Due to the mass of the dies, etc., expanded metal machines have, for the most part, operated at relatively slow speeds.

One other factor entering into the construction of most machines built in the past was that the ultimate utilization of the expanded metal did not require the holding of close tolerances and, therefore, machines capable of maintaining a reasonable tolerance were commercially acceptable. Nowadays, expanded materials are being used in applications requiring a high degree of accuracy. Some materials are now being expanded which are only a few ten-thousandths of an inch in thickness and it is anticipated that future applications of such materials will require an expansion of materials of even less thickness.

Many present day applications of expanded materials still do not require extreme accuracy, but competition between manufacturers has demanded better accuracy and has forced the maintenance of price levels while labor and machine costs have risen rapidly. Therefore, it has been necessary to find a faster and more economical way to produce expanded materials. High speed machines, which seem to be the most logical way of producing more expanded material for approximately the same cost, require automatic control because the operator is unable to react fast enough to consistently obtain the desired result.

Another factor influencing the cost of expanded materials is the quantity of waste formed during the manufacturing process. If the final form sheet is to have closed ends, production of a sheet with open ends necessitates an additional cutting operation to remove the excess material. The extra cutting operation required not only wastes material, but also increases the labor cost due to the time involved.

This invention contemplates an improved machine for expanding material which includes a vertically movable ram, a fixed die, and a horizontally movable die mounted on the ram and adapted to mate with the fixed die to form the material which is placed therebetween. Apparatus is provided which controls the movement of the material to be formed through the machine. The control system provided includes apparatus necessary to automatically stop and start the movement of the material through the machine in response to a preset signal which, in most instances, will be a function of the length of material to be produced. After the movement is stopped, means are provided in the machine to auto matically perform the cut-off operation and subsequently restart the movement of the material through the machine.

One object of the invention is to provide an improved material forming machine which will operate at high speeds and at the same time with a high degree of accuracy.

Another object of the invention is to provide an improved material forming machine which will automatically produce predetermined lengths of expanded materials.

Still another object of the invention is to provide an improved material forming machine which automatically produces expanded material of a given length having closed ends.

A further object of the invention is to provide an improved material forming machine which can selectively produce expanded materials in one continuous piece or can continuously produce expanded materials of predetermined lengths.

A still further object of the invention is to provide an improved material forming machine which can be preset to perform a selected number of operations on the material, after which the material is severed and a new cycle automatically begun.

The foregoing additional objects and advantages of the invention will become more apparent when the following description is read in conjunction with the accompanying drawings wherein like reference characters denote like parts in all views, and wherein:

FIG. 1 is a front elevation view of a material forming machine constructed in accordance with the invention and having portions of the structure broken away to illustrate the details thereof;

FIG. 2 is an enlarged partial vertical cross-sectional view taken along the line 2-2 of FIG. 1;

FIG. 3 is an enlarged view of a portion of the righthand end of the machine of FIG. 1, and illustrates a portion of an indexing system for the movable die;

FIG. 4 is an enlarged view of a portion of the lefthand end of the machine of FIG. 1, illustrating a portion of the indexing system for the movable die;

FIG. 5 is an enlarged elevation view of the right-hand end of the machine shown in FIG. 1;

FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 5, with the driving chain removed. for clarity of illustration;

FIG. 7 is an enlarged elevation view, partly in section, illustrating the mechanism for adjusting the extent of indexing of the movable die;

FIG. 8 is a cross-sectional view taken along line 8-3 of FIG. 7;

FIG. 9 is a view, partly in cross-section, of one of the cams taken along the line 9-9 of FIG. 1;

FIG. 10 is a view illustrating an expanded material having closed ends;

FIG. 11 is a view illustrating an expanded material having open ends; and,

FIG. 12 is a schematic diagram illustrating the arrange ment of the control circuit useful in connection with the machine shown in FIG. 1.

Referring to the drawings in detail, and particularly to FIG. 1, reference character 10 generally designates a metal fonming machine constructed in accordance with the invention, and which includes a suitable power unit 12 positioned at one end of the machine, The power unit 12 may be of any desired construction and may utilize any desired driving mechanism, such as an electric motor, and is therefore not shown in detail herein.

The main frame 14 of the machine 10 may be formed as a single large casting and is provided with vertically extending end plates 16 and 18 at the opposite ends thereof. Flanges 20 extend outwardly from the end plates 16 and 18 to provide covers for the machine and indexing systems of the machine, which will be described below. The end plates 16 and 118 are interconnected by an arcuate section 22 at the top of the machine which provides protection for parts of the operating portions of the machine and enhances the overall appearance thereof. A cross member 24 is also positioned at the lower end of the machine to interconnect the end plates 16 and 18.

The main drive shaft 26 of machine 10 extends lengthwise through the upper portion of the machine between the end plates 16 and 18. The shaft 26 extends through the end plate 16 to receive a pulley or the like 28. A belt or the like 30 extends from the power unit 12 over the pulley 28 to turn the drive shaft 26 and operate the remainder of the machine, as will be described below.

The opposite end portions of the drive shaft 26 are journaled in suitable bearings 32 slidably supported for vertical movement by guides 34, which are preferably cast integrally with the frame 14. The bearings 32 and guides 34 are also illustrated in FIG. 6. Each bearing 32 is positioned by means of a screw 36 threaded through the upper portion 22 of the frame 14. Suitable handle-s 38 are provided on the upper end of each screw 36 and a lock-nut assembly 40 is provided on each screw 36 in contact with the top portion 22 of the frame 14 to lock the screws 36 in the desired positions. Each screw 36 extends downwardly into contact with the upper end of the respective bearing 32 to adjust the height of the respective bearing 32 and hence the height of the respective end portion of the drive shaft 26, The drive shaft 26 is constantly urged upwardly, as will be described, such that the screws 36 will be adjusted to position the drive shaft 26 horizontally or tilted at any desired angle, depending upon the forming operation taking place.

A series of cams 42 are mounted in longitudinally spaced relation around the drive shaft 26 to provide reciprocation of a ram 44. Each cam 42 has a single lobe thereon as shown in FIG. 9, and all the lobes of the cams 42 are aligned along the length of the drive shaft 26 to act in unison, forcing the ram 44 downwardly fora forming or expanding operation. It will also be noted that each cam 42 slides over a pad 46 mounted on top of the ram 44 to provide good bearing surfaces between the cams and the ram.

As shown in FIGS. 3, 4 and 5, a pair of plates 48 are secured to each end of the ram 44 and extend through the vertical slot 50 in the respective frame end plate 16 or 18. Each pair of plates 48 are extended vertically and are spaced apart a sufiicient distance to slide along the opposite sides of respective slot 50 to guide the ram 44 during the vertical reciprocating movements of the ram, as will be described. A block 52 is secured to the lower ends of each pair of plates 48 and a mating block 54 (FIG. is provided on the respective end plate 16 or 18 below the slot 50. A plurality of compression springs 56 are anchored between each pair of blocks 52 and 54 to resiliently support the opposite ends of the ram 44 and constantly urge the ram upwardly. Each spring 56 is provided with a mod guide 58 extending therethrough to maintain the springs in the desired operating positions. Thus, the drive shaft 26 moves the ram 44 downwardly through the medium of the cams 42 and support pads 46 once each revolution of the drive shaft 26, and the springs 56 return the ram 44 upwardly to maintain the ram in constant sliding contact with the cams 42.

A microswitch 59 is mounted on a bracket 61 which is fixed to the end plate 18. As may be clearly seen in FIG. 5, a cam 63 is attached to the end of the block 52 in such a position that the cam 63 will engage and actuate the microswitch 59 during the downward movement of the ram 44. Also shown are a pair of electrical conductors 67 and 69, which will be described in connection with FIG. 12.

As shown in FIG. 2, the ram 44 is substantially rectangular in vertical cross-section, and is disposed above a stationary bed 60, with the side 62 of the ram adjacent the bed 60 being offset or spaced horizontally from the adjacent side 64 of the bed 66. The bed 64 is suitably secured in a fixed position on the frame 14 of the machine ftl and extends horizontally along the length of the frame 14 between the end plates 16 and 18. A groove 65 i formed in the face 62 of the ram 44 at the lower end of the ram and along the length of the ram to provide a flat shoulder or surface 66 facing in the direction of the bed 66 and a downwardly facing shoulder 68. A shuttle bar 70 is positioned to slide on the shoulders 66 and 68 lengthwise along the ram 44 and is held is sliding engagement with the shoulders by a bolt 72. The bolts 72 extend through elongated slots 74 (FIGS. 3 and 4) which extend through the shuttle bar 70. Thus, the shuttle bar 70 is held in the desired vertical position against the shoulders 66 and 68 but yet can slide lengthwise with respect to the ram 44.

A movable die 76 is suitably secured to the lower end of the shuttle bar 70, such as by bolts (not shown). A mating die 78 is secured to the upper end of the stationary bed 66. The movable die 76 is secured in a groove 80 in the lower end of the shuttle bar 76 to transfer all forces imposed on the die 76 through the shuttle bar 76. The lower stationary die 78 is securing in a mating groove 79 in the bed 60 and is held in rigid position by a plurality of bolts 82.

The mating dies 76 and 78 may take any desired form, depending upon the shape desired in the finished expanded metal product being formed from a sheet of material. In any event, substantial forces are imposed on both of the dies 76 and 78 when the movable die 76 is moved downwardly to engage the sheet metal 84. These forces are effectively taken care of in the tationary die 78 by the rigid coupling thereof to the bed 66 by the bolts 82. However, the forces imposed on the movable die 76 tend to tilt, or cant, the die 76 and the corresponding shuttle bar 70 in a direction to move the shuttle bar 70 away from the shoulder 66 of the ram 44. To counteract this tilting force, a plurality of bracing members 86 are provided.

Each bracing member 86 comprises a structurally strong bracket 88 secured to the face 62 of the ram 44 by a pair of bolts 96 directly above the slot 74 receiving the shuttle bar 70. Each bracket 88 extends downwardly and is provided with a slot 92 therein facing the respective side of the shuttle bar 70. A yoke 94 is slidingly disposed in each slot 92 and is provided with a roller 96 journal-ed in the ends thereof. The roller 96 is supported to rotate about a vertical axis. An adjusting screw 98 is threaded through the bracket 88 into contact with the yoke 94 for forcing the respective roller 96 into contact with the adjacent face of the shuttle bar 7t) and thereby urging the shuttle bar 70 against the shoulder 66 of the ram 44. Thus, forces tending to tilt the movable die 76 and shuttle bar 76 are effectively counteracted through the roller 96, yoke 94, and bracket 88. It will also be noted that the roller 96 provides a minimum restrlction to the lengthwise indexing move ment of the shuttle bar 70 which is provided by another mechanism to be described. The adjusting screw 98 may be easily adjusted to retract the roller 96 from the shuttle bar 76 when the dies are to be changed. The ability to retract the rollers 36 greatly facilitates the die changing operation. As illustrated in FIG. 1, there are provided four of the brackets 88 disposed along the length of the ram 44 in a machine of substantial size to effectively prevent tilting or canting movement of the movable die 76.

As previously indicated, the shuttle bar 70 and movable die 76 are reciprocated or indexed lengthwise on the ram 44 during operation of the machine 10. This indexing movement is controlled by a cam and lever system to precisely control the extent of indexing and the time of indexing with respect to the vertical reciprocating movements of the ram 44. As shown in FIGS. 5 and 6, the end portion 164 of the main drive shaft 26 opposite the end of the drive shaft having the pulley 28 thereon, is reduced in diameter and extended through the respective frame end plate 18. A sprocket 182 is mounted on the shaft end portion 100 to drive an endless chain 104. The chain 164 extends over a sprocket 106 mounted on a first cam shaft 168, a sprocket 11%) mounted on a second cam shaft 112, and an idler sprocket 114. It will be apparent that the idler sprocket 114 is secured to the frame end plate 18 by an arm 116 in order that the position of the sprocket 114 can be varied to control the tension imposed on the chain 104. It will also be apparent that, on rotation of the main shaft 26, the sprocket 162 will drive the cam shaft 1118 and 112 through the medium of the endless chain 104 and the sprockets 186 and 116 in timed relation to the rotation of the main drive shaft 26.

The first cam shaft 108 is journaled in the frame end plate 18 and in an arm 118 secured to the frame 14 whereby the cam shaft 168 is rotatably supported parallel with the main drive shaft 26. A cam 120 is rigidly secured on the cam shaft 108 and is provided with a tapered outer face 122 for controlling the movement of a cam follower 124. It will be noted that the sprocket 106 on the cam shaft 108 is of a size with respect to the sprocket 102 on the main drive shaft 26 to rotate the cam 1211 once for each two revolutions of the main drive shaft 26. The face 122 of the cam 120 is tapered outwardly from the center of the cam to the outer edge thereof around a portion of the circumference thereof to force the cam follower 124 outwardly with respect to the frame end plate 18 during a limited portion of each revolution of the cam 126. Thus, the follower 124 is moved outwardly for a limited period of time during each revolution of the cam 120 and is in a retracted position during the remaining portion of the respective revolution of the cam 120. It will be understood that the cam surface 122 is sloped gradually to provide a smooth reciprocating movement to the follower 124. However, since the cam surface 122 is tapered outwardly from the central portion of the cam, the follower 124 will be moved outwardly a distance depending upon the radial position of the follower with respect to the cam 120. That is, when the follower 124 is near the outer edge of circumference of the cam 120, the follower will be moved further from the end plate 18 than when the follower is near the central portion of the cam. Thus, the extent of movement of the follower 124 is controlled by the relative position of the follower with respect to the cam 120. The positioning of the follower 124 is possible due to the construction of the follower, which is illustrated in FIGS. 7 and 8.

The follower 124 comprises a housing 126 having an elongated slot 128 in the side thereof facing the cam 120. The housing 126 is supported on one end of a lever 136 (FIG. 6) in such a manner that the slot 128 extends radially with respect to the cam 126. A threaded positioning shaft 132 is suitably journaled in the opposite ends of the housing 126 and has a control knob 134 on one end thereof to control the position of the shaft. A yoke 136 is constructed to slide along the housing 126 and has a shank portion 138 extending through the slot 128 into sliding contact with the walls of the slot 128. The shaft 132 is threaded through the shank 138. The arrangement is such that the yoke 136 will be moved along the slot 128 in the housing 126 upon turning of the shaft 132. A suitable roller 140 is journaled in the yoke 136 in a direction to make rolling contact with the tapered face 122 of the cam 120 during rotation thereof. Thus, when the extent of movement of the cam follower 124 is desired to be increased, the knob 134 is turned in a direction to move the yoke 136 and the roller 140 nearer the outer circumference of the cam 120, and vice versa.

The lever (FIGS. 5 and 6) is pivotally supported for movement of the follower 124 toward and away from the frame end plate 18 by a shaft 142 extending through the central portion of the lever 130 from brackets 144 mounted on the frame end plate 18. The end 146 of the lever 130 opposite the end having the follower 124 is provided with a pushrod 148 (FIG. 3) extending toward the respective end of the shuttle bar 70. It will also be noted that the outer end of the pushrod 148 is rounded for sliding contact with the vertically extending flat surface 156 of a head 152. The head 152 is mounted on a rod 154 extending from the respective end of the shuttle bar 70 between the guide plates 48 of the ram 44 to position the head 152 outwardly of the supportingstructure for the ram 44. The face of the head 152 is of a size to provide contact with the pushrod 148 in all positions of the shuttle bar 70 and ram 44. In other words, since the ram 44 and shuttle bar 71) are reciprocated vertically during operation of the machine, the face 150 of the head 152 must be of a size to maintain contact with the pushrod 148 during this reciprocating movement. The pushrod 148 stays at substantially the same level during operation of the machine. It will be apparent that when the lever 130 is pivoted by outward movement of the cam follower 124 the pushrod 148 is forced against the face to urge the head 152, rod 154, and shuttle bar 76 in the direction of the opposite frame end plate 16. Since the shuttle bar 70 is mounted on the ram 44 by means of the bolts 72 and slot 74, the shuttle bar is free to move lengthwise to a limited extent.

Return movement or indexing of the shuttle bar '70 and the movable die 76 is provided by a spring 156 provided at the opposite end of the machine from the lever 136. As shown in FIG. 4, the spring 156 is anchored between a plate 158 rigidly secured to the respective guide plates 48 in the respective end of the shuttle bar 70 to constantly urge the shuttle bar 7 0 toward the frame end plate 18. Also, a suitable guide rod 160 is preferably extended through the spring 156 to maintain the spring 156 in the desired position. Thus, when the head 152 is released by the pushrod 148 (by reason of the follower 124 being in contact with the flatter portion of the cam 120) the spring 156 moves the shuttle bar '70 and die '76 back toward the frame end plate 18. As previously indicated, the follower 124 is moved outwardly once each revolution of the cam 120. Thus, the pushrod 148 moves the shuttle bar 70 and die 76 toward the end plate 16 for a limited portion of each revolution of the cam 120, and the spring 156 moves the shuttle bar 70 and die 76 back toward the end plate 18 as soon as the head 152 is released by the pushrod 148. As also previously indicated, the cam 120 is turned once for each two revolutions of the main drive shaft 26, such that the movable die 76 will be indexed into its alternate position each two vertical reciprocating movements of the die.

The relative position of the cam 120 with respect to the cams 42 on the main drive shaft 26 is such that the movable die 76 is in its position nearest the end plate 18 when the ram 44 is moved downwardly to engage the mating die 78. The movable die 76 is shifted toward the end plate 16 when the ram 44 is raised, and is held in such position during the next downward movement of the ram 44. When the ram 44 is again raised, the movable die 76 will be shifted back to the position nearest the end plate 18.

As can be seen in FIGS. 5 and 6, a microswitch 163 is attached to a bracket 165 which is in turn fixed to the bracket 144. A plate 167 is fixed to the lever 130 in such a position that it will actuate the microswitch 163 when the movable die 76 is moved to a position nearest the end plate 16. A pair of electrical conductors 169 and 171 extend from the microswitch 163. The purpose of the conductors 169 and 171 will be explained in connection with the circuit diagram shown in FIG. 12.

The second cam shaft 112 is also journaled in the end plate 18 and in an arm 162 extending from the frame 14 so that the shaft 112 is in a position parallel with the main drive shaft 26, As can be seen in FIGS. 1 and 2, a feed roller 164 cooperates with an idler roller 166 in feeding the material 84 over the bed 60, as will be described. A cam 168 is rigidly secured on the calm shaft 112 and has a tapered outer surface 178 arranged eccentrically with respect to the cam shaft 112. A second cam follower 172 is supported on the upper end of a second lever 174 in contact with the tapered surface 178 of the cam 168 to pivot the lever 174 in accordance with the position of the cam. The follower 172 is mounted on an adjusting screw 176 which extends through the lever 174. The adjusting screw 176 is provided to adjust the position of the follower 172 with respect to the tapered surface 170 of the cam 168. It will be observed in FIGS. 5 and 6 that the tapered surface 171 of the eccentric portion of the cam 168 is tapered outwardly toward the end plate 18, such that the extent of the movement of the lever 174 will be increased as the follower 172 is moved toward the end plate 18.

The lever 174 is pivotally supported at its central portion by a bracket 178 extending from the end plate 18. A roller 180 is provided on the lower end of the lever 174 to contact an upwardly extending lever 182 forming a part of a suitable one-way clutch assembly 184.

The clutch assembly 184 is connected to the feed roller 164 and operates to drive the feed roller 164 in unidirectional feeding rotation and to prevent a reverse turning of the feed roller 16 4. Feeding of the material 84 is obtained when the lever 182 is driven in the counterclockwise direction as viewed in FIG. 5.

The power unit 12 is connected to the feed roller 164 through the one-way clutch assembly 184 for intermittent rotation of the roller 164. As the particular construction of the operating mechanism of the clutch assembly 184 forms no part of this invention, and as such mechanisms are well known, it is believed that further description of the clutch assembly 184 is unnecessary. A spring member 186 is attached to the arm 182 of the oneway clutch assembly 184 to bias the lever 182 into continual engagement with the roller 188 of the lever 174. The opposite end of the spring member 186 is attached to a bracket 188 which is fixed to the end plate 18. The spring 186 also serves the purpose of maintaining the cam follower 172 in constant engagement with the face 170 of the cam 168.

When the roller 180 is moved to the left as viewed in FIG. 5, the lever 182 is pivoted counterclockwise to actuate the one-way clutch 184 and turn the feed roller 164 a predetermined number of degrees. When the roller 180 is moved to the right as viewed in FIG. 5, the lever 182 is moved clockwise in following relation with the roller 180 by the spring 186. The clutch assembly 184 operates in the usual manner to prevent turning movement of the feed roller 164 during the clockwise movement of the lever 182.

It will also be noted that the extent of movement of the lever 182, and hence the degree of rotation of the feed roller 164, is controlled by the extent of pivotal movement of the lever 174. The movement of the lever 174 is determined by the position of the follower 172 with respect to the cam 168. It will be further noted that the lever 174 is pivoted once for each revolution of the cam 168, which, in turn, is rotated simultaneously with the main drive shaft 26. The timing of the rotation of the cam 168 with respect to the cams 42 on the main drive shaft 26 is such that the feed roller 164 is turned each time the ram 44 is raised to disengage the dies 76 and 78 to index or feed the material 84 a predetermined distance over the bed 60.

A brake assembly 198 which is shown clearly in FIG. 5, is associated with the drive roller 164 to prevent the clockwise movement of the lever 182 when the brake assembly 198 is engaged. As shown therein the brake assembly 190 includes a conventional brake shoe arrangement 192 which is spring loaded as at 194 so that the amount of braking force imparted by the brake assembly 190 can be controlled. The brake 190 is adjusted in this manner so that a complete feed of the material 84 will occur even though the machine 10 is shut down in the middle of a stroke of the ram 44. Release of the brake assembly 190 is accomplished by means of an electrical solenoid 196 acting through a linkage arrangement 198. As shown in FIG. 5, a pair of electrical leads 2% and 282 extend from the solenoid 196. The purpose of the electrical leads or conductors will be explained in connection with FIG. 12. The spring 194 is adjusted until the frictional force imparted by the brake shoe 182 on the drive roller 164 is :sufiicient to prevent clockwise rotation of the lever 182 due to the biasing force of the spring 186, but is sufficiently light so that the lever 174 through the roller can drive the lever 182 and consequently the roller 164 in the counterclockwise or material feeding direction.

Turning now to FIG. 12, shown therein is an electrical circuit associated with controlling the feeding or movement of material 84 through the machine 11). As shown therein, a source of electrical potential 284 is connected with the solenoid 1% by means of the conductor 282 and with a switch 206 by a branch conductor 288. The switch 206 is of the three-position type having an off position and two operating contacts designated by the reference characters 216 and 212, respectively. The contact 212 is connected with the microswitch 1 63 by means of the conductor 162. The conductor 171 which is connected with the microswitch 163 is connected with a relay 214 which includes three sets of contacts 216, 218 and 228. Conductors 222 and 224 connect the conductors 169 and 171 with opposite sides of the contacts 216, respectively. The source of electrical potential 204 is connected by means of a conductor 226 and a branch conductor 2 28 with the relay 214. The contacts 218 in the relay 214 are connected by means of a conductor 238 with the conductor 226 and by means of the conductor 206 with the solenoid 196 of the brake assembly 198.

It can thus be seen that the electrical circuit is complete for the purpose of continuously producing the expanded material when the switch 286 is moved to a position closing the contact 2112 thereof. With the switch 206 in this position, closing of the microswitch 1163 by the movable die 76 energizes the relay 214 which closes the contacts 216 and 218. Closing of the contacts 216 completes a circuit through the conductors 222 and 224, maintaining the relay 214 energized and holding the contacts 218 closed until the circuit is interrupted by moving the switch 286 to the off position, or to any position opening the contact 212. When the contact 21 8 is closed, the solenoid 196 of the brake assembly is actuated due to the completion of the circuit through the conductors 202, 200, contacts 218, conductor 238 and conductor 226. As previously pointed out, actuation of the solenoid r126 releases the brake 190, permitting the counterclockwise or feeding rotation of the feed roller 164 as the machine is operated. As indicated, the circuit remains closed until it is manually broken by an interruption in the circuit such as by moving the switch 206, opening the contact 2 12. Opening and closing of the microswitch 163 will have no effect upon the circuit after the contacts 216 of the relay 214 are closed, due to the shunt circuit provided by the conductors 222 and 224.

The contact 210 of the switch 286 is joined by a conductor 232 to contacts 234 which are located in a relay 236. The relay 236 is of the time relay type and is ar ranged so that the contacts 234 are normally closed.

When the relay 236 is energized, a finite time passes before the contacts 234 are opened. After the contacts 234 have been open for a period of time, the relay 236 automatically returns the contacts 234 to the closed position. The contacts 234 are connected with a counting mechanism 238. While the counting mechanism 233 is shown schematically, it should be pointed out that it is of the reset type which may have a predetermined number of operations set therein, after which it will automatically reset and begin an additional sequence of the preset number of operations.

As shown in FIG. 12, the counting mechanism 238 includes an electrically energized clutch means 240, a counter 242, and a pair of contacts 244 and 246. The contacts 244 may be considered as normally open, and the contacts 246 may be considered as normally closed. A conductor 248 connects the normally closed contacts 234 of the relay 236 with the normally closed contacts 246 of the counting mechanism 238. The opposite side of the contacts 246 are connected to the conductor 222 by a conductor 250. A branch conductor 252 connects the conductor 248 with the normally open contacts 244 in the counting mechanism 238. The contacts 244 are also connected by means of a conductor 254 with the relay 236. A conductor 256 connects the relay 236 with the conductor 226 which is in turn connected with the source of electrical potential 204, thereby completing the circuit through the relay 236. A branch conductor 258 connects the clutch 240 with the conductor 248 and, as can be seen in the circuit diagram of FIG. 12, the clutch 240 and counter 242 are connected within the counting mechanism 238 by a conductor 260. The conductor 260 is in turn connected with the conductor 226 which is connected with the source of electrical potential 204. The conductor 67 is connected with the conductor 248 and with the microswitch 59 which is associated with the ram 44. The conductor 69 which is connected with the microswitch 59 is connected at the other end with the set of contacts 220 in the relay 214. A conductor 262 connects the opposite side of the contacts 220 with the counter 242 in the counting mechanism 238, thereby placing the contacts 220 in a series relationship with the microswitch 59.

It should be pointed out that the m icroswitches 59 and 163 may [be interchanged so that the microswitch 163 which is associated with the shuttle bar 70 may be associated directly with the counter 242; and the microswitch 59 which is associated with the ram 44 may be placed in the circuit so that it is in series with the relay 2:14. -It should also be pointed out that the counting mechanism 238 is a commercially available item and therefore is shown only in the schematic arrangement. The preferred counting mechanism 238 is an arrangement B 242, of the HZ series Microflex Reset Counter manufactured by the Eagle Signal Company of Moline, Illinois.

FIGS. and 11 are provided to illustrate the diiference between the expanded material produced with closed and open ends, respectively. As can be seen in FIG. 10, the material 84 includes a first strand 270 which is closed at each edge of the material as shown at 272. Comp-aring the closed portions 272 with the material 84a of FIG. 11, it can be seen that the first strand 270a includes a pair of projecting ends 272a at each side of the material. Very often it is desired in producing expanded material that the loose ends should not be projecting because of the sharpness thereof and the danger of injuring a person handling the material.

FIG. 10 also aids in illustrating the diiference between the process of counting strands and counting diamonds. As shown in FIG. 10, the strands of the material are illustrated by the reference characters 270, 274, 276 and 278. These reference characters designate four consecutive strands of the material. At times it may be desirable to count the number of diamonds formed rather than 10 the number of strands formed. When counting diamonds, it can be observed in FIG. 10 that the diamonds 280 and 282 which are formed by the strands 270, 274, 276 and 2'78 would be considered as first and second diamonds, respectively. It can be seen, therefore, that it takes two strands for each diamond.

In summarizing the operation of the machine 10, it will be noted that the power unit 12 drives the main drive shaft 26 to reciprocate the ram 44 through the cams 42 and springs 56 at the opposite ends of the ram. Each time the ram 44 is lowered, the mating dies 76 and 78 form the sheet metal 84 being fed over the bed 60 by the feed roller 164 and idler roller 166. Each time the ram 44 is raised to disengage the dies 76 and 78, the movable die 76 is indexed lengthwise and the sheet metal 84 is indexed part way through the machine. The movable die 76 is indexed first in one direction and then in the other to provide the desired forming operation on the sheet metal 84- and produce the expanded metal product.

While the foregoing is a description of the general operation of the machine, it should be pointed out that the switch 206 controls the operation of the machine in either an automatic position wherein the contact 210 is closed, or in a manual position wherein the contact 212 is closed. With the machine running and the switch 206 in the automatic position closing the contact 210, energy is supplied through the conductor 232 to the normally closed contact 234 of the relay 236. With the switch 206 in this position, it can be seen that no energy reaches the relay 214, except through the conductor 248, the normally closed contacts 246, and the conductor 250 which is connected to the conductor 222.

At this point in the operation of the machine 10, no material feed can take place because the brake is still applied to the feed roller 164. When the movable die 76 reaches the leftmost end of its travel, it can be seen in FIG. 6 that the microswitch 163 will be actuated due to the contact thereof with the plate 167 mounted on the lever 130. When the microswitch 163 is closed, current will be supplied through the conductors 222, 169, the microswitch 163, and the conductor 171 to the relay 214 which will close the contacts 216, 218 and 220 therein. Upon the closing of the contacts 218, energy is supplied through the conductor 200 to the solenoid 196 releasing the brake 190 and thereby permitting the feed roller 164 to advance material 84 through the machine 10.

Due to the simultaneous closing of the contacts 216 with the contacts 218 of the relay 214 it can be seen that a shunt is provided around the microswitch 163 by the conductor 224 so that the relay 214 will remain energized until an interruption in the shunt circuit occurs.

A preset number of operations, in this case a predetermined number of strands of expanded metal to be formed, is placed in the reset type counting mechanism 238. Since the contacts 220 are closed, the circuit through the conductor 67 will be completed with the counter 242 each time the microswitch 59 is closed by the downward movement of the ram 44 and the cam 63 associated therewith. Each time the microswitch 59 is actuated one count is placed in the counter 242. Upon reaching the preset number of strands, the counting mechanism 238 is automatically actuated to close the normally open contacts 244 and open the normally closed contacts 246. Opening of the normally closed contacts 246 interrupts the circuit to the microswitch 163 so that when the microswitch 163 is opened by movement of the movable die 76 to the right, the circuit to the relay 214 is interrupted and the contacts 216, 218 and 220 are opened.

Opening of the contacts 218 interrupts the circuit to the solenoid 196 of the brake shoe 194 and permits the reactuation of the brake 190, stopping the .material feed by the roller 164. Closing the normally open contact 244 transmits current to the relay 236 through the conductor 254-. As previously described, the relay 236 holds the contacts 234 closed for a finite period of time, then opens the contacts 234-, interrupting current flowing to the counting mechanism 238. The interruption of the current to the counting mechanism 233 permits the automatic resetting of the counter 242. After another finite period of time, the relay 236 automatically closes the contacts 234. Upon closing of the contacts 234, current is again supplied to the counting mechanism 238 and the sequence of operation begins again.

t should be pointed out that the apparatus is so constructed that with the first stroke occurring with the movable die 76 in the leftmost position, as viewed in FIG. 1, closed ends such as shown in FIG. at 272 will be produced. Also, with the microswitch 163 controlling the operation of the brake 190, the counter 242 will indicate the number of strands made.

Should it be desired to count diamonds, the microswitch 163 can be substituted for the microswitch 59, and vice versa. With this arrangement of microswitches, it can be seen that the brake 1% will be released as the arm 44 moves downwardly. Therefore, it is not possible to maintain the ends of the material closed. The diamond count occurs because the counter 242 will be actuated by the microswitch 163 every other time that the ram 44 travels downwardly.

One of the reasons for the use of the time delay relay 236 is to permit sufficient time to elapse between the end of the production of one sheet of expanded material and the beginning of the next sheet for the brake 1% to be applied, preventing feeding of the material 844 through the machine 10 until at least two strokes of the ram can be made. As can be realized from the foregoing, two strokes of the ram will sever the material 84, providing a smooth edge at the end of the foregoing portion of material and for the beginning of the next portion of material to be produced. The time delay relay 236 also provides a sufficient delay in closing the contacts 234 to allow the counting mechanism 238 to reset completely.

From the foregoing it will be apparent that the present invention provides a structurally strong metal forming machine having a high degree of precision in operation. The movable die is indexed a precise distance in precisely timed sequence with the engaging and disengaging of the dies. The extent of indexing of the movable die and the sheet metal being fed through the machine is easily adjusted with a minimum of time. It will further be noted that the movable die is effectively supported against tilting without interference with the indexing movements thereof.

It should also be observed that the switch 206 and the circuits associated therewith provide a means of selec tively producing a continuous length of expanded metal depending only upon the total length of the material 84 which is fed thereto, or producing continuously a multiplicity of sheets having a preselected number of operations performed thereon. It should also be pointed out that if desired, the final form of the expanded metal can include closed ends.

It should be understood that the foregoing specific embodiment is by way of example only in that many changes and modifications can be made therein without departing from the spirit of the invention or the scope of the an nexed claims.

What we claim is:

1. In a material forming machine having a vertically movable ram, a fixed die, a horizontally movable die located on the ram and adapted to mate with the fixed die to form a sheet there'between, the improvement comprising:

sheet advancing means adapted to feed the sheet through the machine in timed relationship with movement of the ram; and,

control means adapted to start and stop said sheet advancing means, whereby formed sheets having a predetermined length are automatically produced.

2. In the material forming machine of claim 1 wherein said control means includes:

brake means operably connected with said sheet advancing means;

brake release means connected with said brake means;

and,

resettaible counter means operably connected with the ram, movable die and brake release means for alternately energizing and tie-energizing the brake release means in a predetermined time sequence for alternately forming a predetermined length of said sheet and severing said sheet.

3. In the material forming machine of claim 2 wherein said control means also includes:

first switch means operably associated with the ram;

second switch means operably associated with the horizontally movable die;

relay means connected in series with said first switch means and with said brake means whereby said brake means is released upon closing said first switch means; and,

means connecting said second switch means with said counter means, whereby said counter means is actuated by the movement of the horizontally movable die.

4. In the material forming machine of claim 3 wherein said control means includes:

a time delay relay means connected in series with said counter means adapted to open momentarily and cause said counter to reset after the predetermined number of operations have been performed.

5. In the material forming machine of claim 2 wherein said control means also includes:

first switch means operably associated with the horizontally movable die;

second switch means operably associated with the ram;

relay means connected in series with said first switch means and with said brake means, whereby said brake means is released upon closing of said first switch means; and,

means connecting said second switch means with said counter means, whereby said counter means is actuated by the movement of the ram.

6. The material forming machine of claim 1 wherein said sheet advancing means includes:

roller means engageable with the sheet adapted to advance the sheet through the machine;

one-way clutch means operably connected with said roller means, whereby said roller means is caused to advance the material in only one direction; and, wherein said control means includes:

brake means 'cooperable with said one-way clutch means and roller means when actuated to permit said clutch means and roller means to be moved to a position of maximum material advance but to prevent further movement thereof; and, means for actuating said brake means.

7. The material forming machine of claim 2 wherein said control means also includes:

first switch means operably associated with the ram;

second switch means operably associated with the horizontally movable die;

first relay means connected in series with said first switch means and having first and second contacts therein adapted to be closed when said first relay means is energized;

brake releasing means connected with said first contacts and operably connected with said brake means, whereby said brake means is released by said brake releasing means upon closure of said first contacts;

resettable counter means connected in series with said second contacts and with said second switch means;

said counter means including a solenoid actuated clutch means, a solenoid actuated count coil connected with said clutch means and with said second contact, a normally open contact, a normally closed contact connected with said first relay means, each adapted to be actuated by said count coil, and means for setting a predetermined number of counts in said counter means, whereby said count coil closes said normally open and opens said normally closed contacts after actuating of said second switch means the predetermined number of counts;

second relay means connected with said normally open contacts and having normally closed contacts therein connected with said clutch means, whereby closing said normally open contacts opens said normally closed contacts in said second relay, thereby resetting said counter means;

said second relay means being constructed to close the normally closed contacts therein after a predetermined time; and,

the arrangement being such that opening the normally closed contacts in said counter means de-energizes said first relay means, thereby opening said first and second contacts and tie-energizing said brake releasing means whereupon said brake means stops the advance of material through said machine and closing of said normally closed contacts in said second relay energizes said counter means returning said contacts therein to their normal positions, whereupon said 'brake means is released when said first switch means is closed.

8. In a material forming machine having a vertically movable ram, a fixed die, a horizontally movable die located on the ram and adapted to mate with said fixed die to form a sheet placed therebetween, and means for advancing the sheet through the machine, the improvement comprising:

a source of electrical potential;

first switch means operably associated with the vertically movable ram whereby said first switch means is closed by the vertical movement thereof;

second switch means operably associated with the horizontally movable ram whereby said second switch means is closed by the horizontal movement thereof; normally engaged brake means adapted to be electrically released, said brake means operably associated with the means for advancing the material through the machine;

manually operated switch means connected with said source of electrical potential;

a normally-closed time delay relay connected with said manually operated switch means and in series with said second switch means;

resetba'ble counter means including a clutch solenoid connected with said time delay relay, a counting solenoid connected with said second switch means and adapted to be actuated each time said second switch means is closed, a normally open contact and a normally closed contact, each adapted to be actuated when said second switch means is closed a predetermined number of times thereby opening said normally closed contact and closing said normally open contact;

means connecting said normally open contact with said time delay relay and with said source of electrical potential;

second relay means having first, second, and third contacts therein, said relay being connected in series with said first switch means and with said source of electrical potential;

means connecting said normally closed contact with said source of electrical potential and with said first contact;

means connecting said first contact with said first switch means whereby said first contact and said first switch :means are connected in parallel;

means connecting said second contact with said source of electrical potential and with said brake means;

means connecting said brake means with said source of electrical potential; and,

means connecting said third contact in series with said second switch.

References Cited by the Examiner UNITED STATES PATENTS 2,620,876 12/1952 Harness et al 72-23 2,694,449 11/1954 Rut-fin 83558 3,181,322 5/1965 Leliacque 72--17 CHARLES W. LANHAM, Primary Examiner. R, D, GREFE, Assistant Examiner. 

1. IN A MATERIAL FORMING MACHINE HAVING A VERTICALLY MOVABLE RAM, A FIXED DIE, A HORIZONTALLY MOVABLE DIE LOCATED ON THE RAM AND ADAPTED TO MATE WITH THE FIXED DIE TO FORM A SHEET THEREBETWEEN, THE IMPROVEMENT COMPRISING: SHEET ADVANCING MEANS ADAPTED TO FEED THE SHEET THROUGH THE MACHINE IN TIMED RELATIONSHIP WITH MOVEMENT OF THE RAM; AND, 